Short-range wireless proximity networks typically involve devices that have a communications range of one hundred meters or less. To provide communications over long distances, these proximity networks often interface with other networks. For example, short-range networks may interface with cellular networks, wireline telecommunications networks, and the Internet.
High rate physical layer (PHY) techniques for short-range proximity networks are quickly emerging. One such technique involves frequency hopping applications of orthogonal frequency division multiplexing (OFDM). This technique involves the transmission of each of the OFDM symbols at various frequencies according to pre-defined codes, such as Time Frequency Codes (TFCs). Time Frequency Codes can be used to spread interleaved information bits across a larger frequency band.
The WiMedia Medium Access Control (MAC) group is developing a MAC layer that would be used with an OFDM physical layer. A current version of this MAC is described by O'Conor, Jay; Brown, Ron (ed.), Distributed Medium Access Control (MAC) for Wireless Networks, WiMedia Technical Specification, Draft 0.98, Aug. 6, 2005 (also referred to herein as the WiMedia MAC Specification v. 0.98).
This MAC layer involves a group of wireless communications devices (referred to as a beaconing group) that are capable of communicating with each other. The timing of beaconing groups is based on a repeating pattern of “superframes” in which the devices may be allocated communications resources.
MAC layers govern the exchange among devices of transmissions called frames. A MAC frame may have various portions. Examples of such portions include frame headers and frame bodies. A frame body includes a payload containing data associated with higher protocol layers, such as user applications. Examples of such user applications include web browsers, e-mail applications, messaging applications, and the like.
In addition, MAC layers govern the allocation of resources. For instance, each device requires an allocated portion of the available communication bandwidth to transmit frames. The WiMedia MAC provides for the allocation of resources to be performed through communications referred to as beacons. Beacons are transmissions that devices use to convey non-payload information. Each device in a beaconing group is assigned a portion of bandwidth to transmit beacons.
Such transmissions allow the WiMedia MAC to operate according to a distributed control approach, in which multiple devices share MAC layer responsibilities. Accordingly, the WiMedia MAC Specification v. 0.98 provides various channel access mechanisms that allow devices to allocate portions of the transmission medium for communications traffic. These mechanisms include a protocol called the distributed reservation protocol (DRP) in which reservations for connections are negotiated among devices. These mechanisms also include a protocol called prioritized contention access (PCA).
As the use of communications networks, such as short-range wireless proximity networks, becomes progressively more prevalent, it is desirable to increase network capacity. Also, it is desirable to accelerate allocation processes for sharing the wireless communications medium, such as DRP mechanisms. Accordingly, techniques are needed to provide such features.